Efeito da moagem de alta energia na microestrutura e nas propriedades magnéticas do compósito wc-10%p.Co

This work a studied the high energy milling effect in microstructure and magnetic properties of the WC-10wt.%Co composite. The composite powders were prepared by mechanical mixed and milled at 2 hours, 100 hours, 200 hours and 300 hours in planetary milling. After this process the composite were compacted in stainless steel die with cylindrical county of 10 mm of diameter, at pressure 200 Mpa and sintered in a resistive furnace in argon atmosphere at 1400 oC for 5 min. The sintered composite were cutted, inlaid, sandpapered, and polished. The microestrutural parameters of the composite was analyzed by X-ray diffraction, scanning electronic microscopy, optical microscopy, hardness, magnetic propriety and Rietveld method analyze. The results shows, with milling time increase the particle size decrease, it possibility minor temperature of sintering. The increase of milling time caused allotropic transformation in cobalt phase and cold welding between particles. The cold welding caused the formation of the particle composite. The X-ray diffraction pattern of composite powders shows the WC peaks intensity decrease with the milling time increase. The X-ray diffraction pattern of the composite sintered samples shows the other phases. The magnetic measurements detected a significant increase in the coercitive field and a decrease in the saturation magnetization with milling time increase. The increase coercitive field it was also verified with decrease grain size with milling time increase. For the composite powders the increase coercitive field it was verified with particle size reduction and saturation magnetization variation is relate with the variation of free cobalt. The Rietveld method analyze shows at milling time increase the mean crystalline size of WC, and Co-cfc phases in composite sintered sample are higher than in composite powders. The mean crystallite size of Co-hc phase in composite powders is higher than in composite sintered sample. The mean lattice strains of WC, Co-hc and Co-cfc phases in composite powders are higher than in composite sintered samples. The cells parameters of the composite powder decrease at milling time increase this effect came from the particle size reduction at milling time increase. In sintered composite the cells parameters is constant with milling time increase

Um olhar sobre as veredas rosianas.

The present work objective to study the configurations that the hinterland it acquires in the workmanship Great hinterland: trails, of Guimarães Rosa demonstrating as this author humanize this element, conferring to it characters universal mystics and through investigations, uncertainties, the auto-corrections of Riobaldo that become hinterland a metaphor of the human interior. Three are the chapters, that they will guide this work: the chapter 1 presents as element key for characterization of the epic one in Great hinterland: trails, the mining hinterland replete of trails, palco of exuberant vegetation, huge and multidimensional scene, where it has an entrecruzamento of fiction and reality. It retakes quarrel of critics as Manuel Cavalcanti Proença, Roberto Schwarz, on the existing epic character in the Great hinterland: trails, constructed from deriving myths of the universal culture, that they had been become popular. The brave and gracious knight, that it has its representabilidade in the popular culture. Thus the medieval hero, the knight represented for the Riobaldo personage, it is cognominado by Proença as Don Riobaldo of the Urucuia, knight of the general fields. O chapter 2 is a study on the popular culture in Rosa and Cascudo. Cascudo the example of Rosa also is exímio studious of the brazilian life, the regionalization and the popular manifestations proceeding from other cultures. O chapter 3 it has as focus of analysis two mitopoéticas personages: Diadorim e Luzia-Homem, which in the cited narratives they generally they assume functions generally atribute the men. Since children, if they dresses male. Valley to point out that Diadorim is not characterized as man, since in Great hinterland:trails if trajaq always as gunman. Luzia, when complete 18 anos pass if to dress as woman, but the stigma of male and female, inherited of the time where it coexisted the father folloies it for all the life. They suffer pain to have been born to fight and to não conhecer to love. They die you deliver the God. This study detects exactly that Diadorim and Luzia-Homem, are personages associates the myths of the universal culture and popular (sphinx, Jellyfish, Venus, Mother d water), that they possess similarities n the archetypes, that transit between the sexos masculine and feminine, without any sexual connotation, possesss it proper code of honr, of this not abdicating ahead of the death. Parallel, in this chapter two cascudianas workmanships willbe studies, that contemplate thematic of the dressed woman of man and being the woman without disguice: the enchantment tale Maria Gomes and romance Flower of tragics romances. The first one will be revisited in order to present subject in Great hinterland:trails through the Diadorim personage. As it will discourse on cases of brave women, cited for Cascudo, immortalized for the tradition, who had made history, that already is not disfarçam of men to carry through acts of bravery and honor.

Caracterização da polpa de pêssegos produzidos em São Manuel-SP

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Captura incidental de um tubarão-baleia, Rhincodon typus (Orectolobiformes, Rhincodontidae), na costa do Ceará, Nordeste do Brasil

A whale shark, Rhincodon typus, was incidentally captured off Ceará on January 2009, during gillnet fishery. This is the second occurrence record for this species off the State and the first including material deposited in a scientific collection.

Manuel d'utilisation de l'Observatoire de l'égalité de genre de l'Amérique Latine et des Caraïbes

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Costa Rica: autoridad social: una larga travesía entre lo ideal y lo posible

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La estrategia de lucha contra la pobreza en Costa Rica: Institucionalidad, financiamiento, políticas, programas

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Costa Rica: proyeccion de la poblacion economicamente activa por regiones, sexo y grupos de edades, 1985-2000

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Costa Rica: crisis, adjustment policies and rural development

Analiza la situacion del sector agropecuario costarricense hasta la decada del 70, los problemas estructurales que mostro el patron de desarrollo seguido, las manifestaciones de la crisis y las caracteristicas de las principales politicas de ajuste que se adoptaron en 1982, asi como el impacto de estas medidas en la agricultura.

Costa Rica: crisis, políticas de ajuste y desarrollo rural

Analiza la situacion del sector agropecuario costarricense hasta la decada del 70, los problemas estructurales que mostro el patron de desarrollo seguido, las manifestaciones de la crisis y las caracteristicas de las principales politicas de ajuste que se adoptaron en 1982, asi como el impacto de estas medidas en la agricultura.

Costa Rica: perspectivas de crecimiento de la población, determinantes demográficos e implicaciones socioeconómicas

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Análisis de la operación interconectada de los sistemas eléctricos de Costa Rica y Panamá

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